"At the moment, 13 are reported dead, 50 others were injured, most of them are teenagers. Reports on casualties are being verified," she said.
"According to preliminary data, 10 people have died," a spokesperson said.
The explosion rocked the vocational college on Wednesday afternoon. A source in local law enforcement agencies said that nearly 70 people were injured in the blast.
The city ambulance service said more than 20 people have been hospitalized.